TR2/3/3A Set Static Timing on TR3B - Car Runs Poorly

[af3683]

My TR3B was running OK until I thought I'd check the timing and try to make it run better. Here is what I did. I lined up the timing marks, checked the point gap, and have the rotor pointing toward #1 spark plug. I then turned the vernier knob to the 3rd division of the scale which is 1 division (4 degrees) retarded from center. Then I used the below "Igition On" method to set the timing and finally turned the vernier knob 1 more division back to the center.

<span style="font-style: italic"><span style="font-weight: bold">Ignition "on" Method

Keep lead from coil to distributor connected.
Clip lead from test light to distributor connector noted above & other lead to Positive (Ground) side of the battery.
Turn ignition on.
If test light is on, turn distributor CCW until light goes off. Then turn distributor CW until light just comes on.
</span></span>

The car starts but will barely stays running. One troubling thing that I have noticed is that prior to messing with the timing the vacuum advance unit was basically parallel with the engine block. After setting the static timing the vacuum advance unit is now pointing toward the front left headlight. This must have something to do with the poor running of the car. I've checked and rechecked mt steps many times and the end result never changes.

I know folks get tired of timing related questions but I'm getting frustrated and would appreciate any help. Thank you.

Art

 

[bobhustead]

Try rotating the distributor back to where the vacuum advance was when you started. Unless you actually pull the distributor from the block and get it back a tooth off, change in the position of the advance should not be perceptible.
Bob

 

[TomMull]

I'd check for actual spark at no. 1 plug in that distributor position. It may be that the dizzy is not really aligned with no 1. Tom

 

[TR3driver]

My guess is that your front pulley has been assembled incorrectly, the timing mark is no longer accurate.

 

[Geo Hahn]

If the timing mark is suspect you may be able to time by ear -- as suggested, putting the distributor back into the original position might get you close enough to dial it in. If that gets it running decently a look with a timing light (to see where the mark is) may be revealing.

A simple piston stop can be made by pounding out the center of a spark plug and threading it to accept a long bolt.

The piston is then <span style="text-decoration: underline">gently</span> offered up to the stop from each direction with the TDC pointer position noted on the pulley each time. Midway between the two resulting marks will be TDC.

 

[af3683]

I only loosened the distributor adjusting clamp and not the bolts that hold it to the block. I know there was a time when I pulled the distributor body out a little bit. Could that have resulted it moving it over a tooth or two? I thought that as long as you didn't remove the bolts that hold it to the block there was only 1 way the distributor could go back in?

Art

 

[TR4nut]

Can't see how you could slip a tooth even if you pulled the distributor body out fully - its the drive gear below that positions everything, so unless it was stuck to the distributor I doubt that is the issue.

My guess is you accidentally rotated the distributor body too much, and you may be timing on the trailing edge of the rotor, not the leading edge. I would orient the distributor closer to what you recollect then try again.

 

[af3683]

Thanks to all. Normally when the pointer and the pully hole are lined up correctly shouldn't the rubbing block be resting on the highest point of the corner of the lobe? If that is true, then even if my pulley was installed incorrectly causing the small hole to be misaligned, shouldn't I be able to turn the engine until the rubbing block is on the highest point of the corner of the lobe near #1 plug and then place a mark on the pulley just below the pointer, ignoring the small hole in the pulley? Correct? Then I could set the static timing with the test light. Thanks agin.

Art

 

[af3683]

I don't think I rotated the distributor body too much. I've been very carefull to stop at the exact moment that the test light comes on. I actually try it numerous times to make sure.

Art

 

[TR3driver]

Thanks to all. Normally when the pointer and the pully hole are lined up correctly shouldn't the rubbing block be resting on the highest point of the corner of the lobe?

No, that is nowhere near the right relationship. With the pointer & hole lined up and the engine turning forwards (there is a fair amount of backlash in the system, so it is important to turn the engine forward to the mark), the cam should just (like 4 degrees earlier) have pushed on the rubbing block hard enough to open the points. Peak lift doesn't happen until many degrees later (roughly 26 degrees at the crank pulley).
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] If that is true, then even if my pulley was installed incorrectly causing the small hole to be misaligned, shouldn't I be able to turn the engine until the rubbing block is on the highest point of the corner of the lobe [/QUOTE]

Also not true. The relationship of the rubbing block, lobe and timing mark is exactly what you change when adjusting the timing. If the timing mark is not accurate, then you have to either go back to piston position as Geo suggested; or give up using the mark and set the timing with either a vacuum gauge or by doing a road test (which is my favorite method of doing the final adjustment anyway, since so many things have changed since the cars were new).

 

[Geo Hahn]

I don't think I rotated the distributor body too much. I've been very carefull to stop at the exact moment that the test light comes on...

But wasn't that process based on the assumption that your pulley was correct and the mark (hole) really is TDC?

If I were doing this I would ignore the book and try to put the distributor back where it started:

...prior to messing with the timing the vacuum advance unit was basically parallel with the engine block...

If it will run there then small rotations of the distributor can be done -- I think you want to find the spot where the idle RPM is greatest, then retard it a bit from there (perhaps enough for a 100 RPM drop).

 

[bobhustead]

The little hole is just a proxy for TDC. You have to find TDC from the crankshaft side of things, using the hole or observed piston and valve position. You can't do it from the distributor side of things. Remember that any of the measured methods of timing are just a starting point. You finish by getting up to about 30 mph and nailing the throttle. If you hear more than 2 or 3 valve train clatters, retard the timing until that is all you hear.
Bob

 

[TR4nut]

I don't think I rotated the distributor body too much. I've been very carefull to stop at the exact moment that the test light comes on. I actually try it numerous times to make sure.

Art

Art-

I made my guess assuming your car ran reasonably well before, but now doesn't - and you said the distributor is now oriented differently. So it sounds to me like it has been moved pretty significantly? Eliminate the thought that it was by accident, perhaps your test procedure is slightly different:

The way I read the static test when the light goes on you have hit just when the points open and you have lost ground on the lead from the coil to distributor. SO the current instead flows through the light - if hooked up in parallel. Did you by chance hook up your test light in series with this lead? That would change the test to finding just when the points close. Just trying to figure out why the distributor position is different now - I don't think you slipped a tooth the way you described your work.

Randy

 

[sp53]

I would suggest you purchase a timing light and dwell meter and see where you are at with this thing. Heck put some gloves on and turn the distributor while it is running, and it will probably be right back where it was when it ran good. In addition, remember that if the points are wrong, they will affect the timing. What are the points set at? Points first then timing, these are simple engines you will not hurt anything by moving the distributor when the engine is hardly running. Play around with it; get a feel for it and then you will understand how to road set the timing.

 

[af3683]

Randy,
Thank you for responding. Sorry for any confusion. When I completed my static timing the orientation of the dizzy was significantly different from the way it was before I messed with it. The car was running decent, but of course that was not good enough for me.

I read up on the proper static timing methods and did the following: Put one lead from test light to distributor connector where the wire from the coil attaches (leaving coil wire connected), put the other lead to positive side of battery (positve ground), turned ignition switch to on, turned distributor CCW until test light went out and then CW until it just came on. I checked this procedure several times and was very carefully to stop turning the dizzy once the test light came on.

The end result was that the dizzy vacuum advance unit was "pointing" toward the from left headlight. Prior to messing with the timing, I recall that the dizzy vacuum advance was basically parallel with the engine block or maybe a hair CW of parallel which seems to be the proper orientation based on photos I've seen. I know many years ago the car was in a front end accident, so it wouldn't surprise me if the pulley was incorrectly installed.

Art

 

[af3683]

As suggested I went out the garage and attempted to orient the distributor the way it was prior to my attempt to static time the ignition. After many attempts at turning the distributor a very small amount at a time, I now have the distributor in a position where the car runs.

I vacuum advance unit is basically parallel with the engine block or maybe a hair CW of parallel which I believe is the proper orientation and the way it was prior to my attempt to static time the ignition. Also, I have the vacuum advance vernier fully retarded which is about where it was before.

I not sure if I should start to mess with the vacuum advance vernier at this point. I do realize that I will need to do the road test to and adjust the vernier.

I have not attempted to drive it yet. Just taking a brake now. I don't have a timing light and am not certain exactly how to use it. A co-worker of mine may have one and I'll ask him tomorrow. Assuming the pulley is not aligned correctly, it sure would be nice to locate the proper point on the pulley to line up with the pointer. I guess the timing light can help locate that point.

Thanks again for all your help. Any additional comments would be appreciated.

Art

 

[TR4nut]

Art-

From what you describe, it certainly sounds like you are static timing it 'by the book'. So yes, if you can grab a timing light it will be interesting to see where that pulley mark shows up. I don't use timing lights much anymore, but I have one of the newer ones now and I have found it useful as it lets me check advance vs rpm - I can see what total advance is doing at 2000+ rpm just to check things.

Randy

 

[af3683]

If I'm able to borrow a timing light, how would I be able to put a paint mark on the pulley for future reference since the timing light is used while the engine is running? Again, I've never used one so this may be a stupid question.

Art

 

[TR4nut]

Art-

Normally I put marks on the pulley prior to using the light then you can use the marks as reference while using the light. Or if you can get hold of one of those newer lights, they let you dial in the advance on the light itself so you still can use the hole in the pulley (assuming it is where it is supposed to be). Randall or someone else I think posted a while back to give a good measure of degrees/inch based on the pulley diameter.

Randy

 

[Geo Hahn]

From some notes I made awhile back:

<span style="font-style: italic">Pulley: Diameter = 5.5”
Circumference = 17.279”
1° = .048”
4° = .192” (13/64”)
24° = 1.15” (1 5/32”)
</span>
That was for a TR4, hence my interest in 24°, but the measurements are the same for the TR3 pulley.

With a timing light with an advance knob you should be able to see how much (if any) the timing hole/mark is off -- then calculate the location of true TDC and try a spot of paint. Once that is dry you can go back to the timing light (set to 0° and see how close you got it.